USOO6469963B1 (12) United States Patent (10) Patent No.: US 6,469,963 B1 Sawada et al. (45) Date of Patent: Oct. 22, 2002

(54) OPTICAL RECORDING MEDIUMAND 5,499.225 A 3/1996 Yoshimura METHOD OF INFORMATION RECORDING/ 5,721.856 A 2/1998 Takeuchi READING AN OPTICAL RECORDING 5,825,726 A 10/1998 Hwang et al. MEDIUM 5.940,853 A * 8/1999 Ooi et al...... 235/454 6,021,103 A 2/2000 Tani (75) Inventors: Yasuo Sawada, Tokyo; Toru Yashiro, 6,198.708 B1 * 3/2001 Suzuki ...... 369/84 X Kanagawa; Eiji Noda, Shizuoka, all of (JP) FOREIGN PATENT DOCUMENTS EP O 552 986 A2 1/1993 (73) Assignee: Ricoh Company, Ltd. (JP) EP O 595 358 A2 10/1993 EP O 704844 A1 9/1995 (*) Notice: Subject to any disclaimer, the term of this EP 0 712 130 A1 11/1995 patent is extended or adjusted under 35 U.S.C. 154(b) by 0 days. OTHER PUBLICATIONS (21) Appl. No.: 09/657,165 Patent Abstracts of Japan, vol. 016, No. 050 (P-1308), Feb. 7, 1992, JP 03 250342 A, Nov. 8, 1991. (22) Filed: Sep. 7, 2000 * cited by examiner Related U.S. Application Data 62) DivisionVision of application No.NO. 09/240,679,of 9, Illedfiled on Feb. 2Z, Primary Examiner-Paul W. Huber 1999, now Pat. No. 6,137,769. (74) Attorney, Agent, or Firm-Dickstein Shapiro Morin & (30) Foreign Application Priority Data Oshinsky LLP Feb. 2, 1998 (JP) ...... 10-020967 (57) ABSTRACT Dec. 17, 1998 (JP) ...... 1O-3591.33 An optical recording medium which includes a PMA area, a (51) Int. Cl." ...... G11B5/09 TOC area, program area, an area that includes a user area (52) U.S. Cl...... 369/47.1 and lead-out area. A portion of the PMA area, which relates (58) Field of Search ...... 369/3201, 47.55, to the program area, is in a recorded State and the TOC area 369/47.12, 47.13, 53.2, 53.24, 53.37, 53.41, is in an unrecorded state. Alternatively, the PMA may be in 53.45, 84, 275.3 an unrecorded State. In addition, a password may be recorded in a portion of an information area. A method of (56) References Cited erasing the medium and a System for reading and recording information are also provided. U.S. PATENT DOCUMENTS 5,337,357 A 8/1994 Chou et al. 1 Claim, 3 Drawing Sheets

START

READING CONTROL DATA OF CD-RW MEDIUM

RECORDING CONTROL DATA N ANOTHER MADIUM OF EXTERNAL DATA STORAGE UNIT

ERASNG CONTROL DATA OF CD-RW MEDUM

ERASING LEAD-OUT AREA CD-RW MEDUM

END U.S. Patent Oct. 22, 2002 Sheet 1 of 3 US 6,469,963 B1

F.G. 1

F.G. 2 U.S. Patent Oct. 22, 2002 Sheet 2 of 3 US 6,469,963 B1

F.G. 3

- 41 erased PMA - 41

erased TOC area 42

program program area area - 43

- 44 erased lead-out area - 44

FG. 4A FIG. 4B

PMA - 41

- 42 program

- 43 area for system information lead-out area - 44

FIG. 5 U.S. Patent Oct. 22, 2002 Sheet 3 of 3 US 6,469,963 B1

62 67

CD-R/RW EXTERNAL UNIT DATA STORAGE UNIT

DISPLAY DISPLAY CONTROL NPUT DEVICE DEVICE | 63 65

F.G. 6

START

READING CONTROL DATA OF CD-RW MEDIUM

RECORDNG CONTROL DAA N ANOTHER MADI UM OF EXTERNAL DATA STORAGE UNIT ERASING CONTROL DATA OF CD-RW MEDIUM ERASING LEAD-OUT AREA CD-RW MEDUM

F.G. 7 US 6,469,963 B1 1 2 OPTICAL RECORDING MEDUMAND PMA 41, the TOC area 42, and the lead-out area 44, are METHOD OF INFORMATION RECORDING/ erased. The user information recorded in the program area READING AN OPTICAL RECORDING 43 remain intact. However, there are no CD drives available MEDIUM which can read the user information Stored in the program area 43, because there is no control data in the filing This application is a divisional application of application information areas. Ser. No. 09/240,679 filed on Feb. 2, 1999, now U.S. Pat. No. Accordingly, there are currently no methods to read user 6,137,769, which is hereby incorporated by reference. information stored in the program area 43 of a CD-RW medium when the medium is accidentally erased by a BACKGROUND OF THE INVENTION quick-erase method. 1. Field of the Invention SUMMARY OF THE INVENTION The present invention relates to an optical recording medium capable of retaining the Secrecy of Stored informa The present invention has been made in view of the tion and to a method of erasing, recording, and reading the above-discussed problems and an object of the present Stored information while retaining a high level of Secrecy. 15 invention is to address and Solve these and other problems. 2. Discussion of the Background The present invention provides an optical recording Optical recording media are disc-shaped media capable of medium which includes an information area. The informa being read and recorded to by optical devices. For example, tion are is comprised of a data area, in which user informa Compact Discs (hereinafter referred to as CDs) such as a tion can be Stored, and a filing information area, in which Compact Disc Digital Audio (CD-DA), a Compact Disc control data for access to the user information can be stored. Read Only Memory (CD-ROM), a Compact Disc Record Initially, the data area is in a recorded State and the filing able (CD-R), and a Compact Disc ReWritable (CD-RW), or information area is in an unrecorded State. large capacity optical recording media Such as a Digital The optical recording medium may further include a Video Disc Read Only Memory (DVD-ROM), a Digital password that is recorded in a portion of the information Video Disc Recordable (DVD-R), and a Digital Video Disc 25 aca. ReWritable (DVD-RW) are well known. These media have The optical recording medium may be a CD-R or a become wide spread as information recording and transmit CD-RW which includes an information area comprising a ting media. In particular, CD-RW media have become data area and a filing information area. The data area remarkably wide spread as erasable/rewrite-able CD media. includes a program area in which user information is Stored When these optical media are used as information trans and a user area in which information can be Stored. The mitting media, it is often important to keep information filing information area contains control data used in acceSS Stored within the media Secret. For example, data Stored in ing the Stored user information. The filing information area a CD can be easily read by a commercially available CD includes a PMA, a TOC area, and a lead-out area. The user drive or CD player. Therefore, a problem which occurs is area, the TOC area, and the lead-out area are in an unre 35 corded State. Both the program area and a portion of the that Secret information is easily leaked when an optical PMA are in a recorded state. The optical recording medium recording medium used to Store the Secret information is may further include a password that is recorded in a portion read by an unauthorized perSon. of the information area. When the medium is used as an The CD-RW media can be reused by erasing information information recording/reading System having System infor which has been Stored. Information erasing methods for 40 mation that is peculiar to the System, the System information CD-RW include a full-erase method in which all the may be recorded in the medium. In this case, the System recorded data is erased and a quick-erase method in which information is used as a password, and the verification of the only control data is erased. Control data is necessary to password may be done by the information recording/reading allow a CD drive to access the information stored in the data System automatically. Specifically, when the System infor area of a CD-RW. The quick-erase method is used in order 45 mation is recorded in the data area, then control data for to quickly make a CD medium ready for rewriting. access to the System information may be further recorded in FIGS. 4A and 4B are schematic diagrams illustrating the PMA. area-structures of a CD-RW medium before and after infor In another aspect of the present invention, an erase mation is erased by a quick-erase method, respectively. A method for erasing CD-RW media is provided, which prior art erase method is described hereinafter referring to 50 includes the Steps of reading control data Stored in a filing FIGS. 4A and 4.B. information area of a CD-RW medium, recording the control In FIG. 4A, reference numerals 41, 42, 43, and 44 data in another medium, and erasing only the control data in designate a program memory area 41 (hereinafter referred to the filing information area of the CD-RW medium. as a PMA), a table of contents area 42 (hereinafter referred In Still another aspect of the present invention, an infor to as a TOC area), a program area 43, and a lead-out area 44, 55 mation recording/reading System is provided which includes respectively. an optical recording medium which includes a file informa User information is Stored in the program area 43 of the tion area. The file information area includes a PMA which is CD-RW medium shown in FIG. 4A and a CD-RW drive in an non-recorded State and a program area in which user gains access to the information in the program area 43 on the information is Stored; a control data Storing medium which basis of control data recorded in the PMA 41. After the 60 Stores control data for access to the user information Stored control data is additionally recorded in the TOC area 42 and in the program area; and a recording device which records the lead-out area 44, the information recorded in the CD-RW the control data in the PMA. The optical recording medium medium becomes capable of being read by a CD drive such as a CD-ROM drive. This recording operation is performed may be a CD-R medium or a CD-RW medium. using a CD-RW drive. 65 BRIEF DESCRIPTION OF DRAWINGS When the described quick-erase method is used, all of the A more complete appreciation of the present invention control data Stored in the filing information areas, i.e., the and many of the attendant advantages thereof will be readily US 6,469,963 B1 3 4 obtained as the same becomes better understood by refer area, the outsider cannot read or play the optical recording ence to the following detailed description when considered medium of the present invention by a CD player or a in connection with the accompanying drawings, wherein: CD-ROM drive. This is because CD players or CD-ROM FIG. 1 is a schematic view illustrating an embodiment of drives cannot read information stored in a CD medium if the optical recording medium of the present invention; 5 control data is not recorded in the TOC area 15. Therefore, FIG. 2 is a schematic view illustrating another embodi the Secrecy of the user information Stored in the program ment of the optical recording medium of the present inven area of the optical recording medium 10 can be maintained against an unauthorized user who does not have a CD tion; Writing drive. FIG. 3 is a schematic view illustrating yet another An authorized user can read the user information by embodiment of the optical recording medium of the present finalizing the optical recording medium using a commer invention which has a high level of Secrecy; cially available CD writing drive. The CD writing drive FIGS. 4A and 4B are schematic diagrams respectively reads the PMA data recorded in the PMA 13 and then illustrating structures of a CD-RW medium before and after records TOC data in the TOC area 15 in accordance with the information is erased by a quick-erase method; 15 PMA data. At the same time, the CD writing drive records FIG. 5 is a Schematic diagram illustrating a structure of an lead-out data in the lead-out area. The medium 10 can now embodiment of the optical recording medium of the infor be read by commercially available CD drives. After this mation recording/reading System of the present invention. finalization of the medium 10, a Selected perSon can read FIG. 6 is a block diagram illustrating another embodiment information Stored in the medium using a CD Writing drive of the information recording/reading of the present inven and a CD player or a CD-ROM drive. tion; and An information transmitting method using Such an optical FIG. 7 is a flow chart illustrating an embodiment of the recording medium 10 is useful for a circle consisting of erase method of the present invention. limited members in which limited user information is dis tributed to the members. The individual member possesses DESCRIPTION OF THE PREFERRED 25 a CD writing drive to read the user information. Information EMBODIMENT providerS Such as a bank, a Stockbrokerage company, or a Referring now to the drawings, wherein like reference research company records user information for the limited numerals designate identical or corresponding parts members in the program area 17 of the optical recording throughout the Several views, and more particularly refer medium 10 as shown in FIG. 1, and distributes the recorded ring to FIG. 1 thereof, there is shown an embodiment of the medium 10 to each member. Because the medium 10 as optical recording medium 10 of the present invention. The distributed cannot be read with a commercially available CD optical recording medium 10 may be, for example, a CD-R player or a CD-ROM drive, secrecy of the distributed medium. Alternatively, the optical recording medium 10 information is secure even when the medium 10 passes into may be a CD-RW medium. At the center of the optical a perSon other than the members, for example, by miscar recording medium 10, a hole 11 is provided which is capable 35 riage or robbery. of receiving the pivot of a CD drive. The optical recording In this case, the information stored in the medium 10 can medium includes an information area comprising a PMA 13, be read if an outsider has a CD writing drive. The present a TOC area 15, a program area 17, and an area 19 which invention provides another optical recording medium includes a recordable user area and a lead-out area disposed detailed below in which information stored therein cannot be one by one from the inside to the outside of the optical 40 read even in Such a case. recording medium. The PMA 13 is further comprised of a FIG. 2 shows another embodiment of the optical record recorded area 52 in which PMA data are recorded and an ing medium 20 of the present invention. At the center of an unrecorded area 50. The TOC area 15 and the area 19 are optical recording medium 20, a hole 21 in which a pivot of also in an unrecorded State. Prescribed user information or 45 a CD drive can fit is provided. The optical recording medium requested user information is Stored in the program area 17. includes an information area having a PMA 23, a TOC area The optical recording medium 10 shown in FIG. 1 25, a program area 27, and an area 29 comprising a record includes the PMA 13, the program area 17 in an recorded able user area and a lead-out area. The medium 20 may state, and the TOC area 15 and the area 19 that are in an further include an additional area Such as a PCA (power unrecorded State and in a record-able State. In addition, the 50 calibration area). The PMA 23 is disposed in an innermost portion 52 of PMA 13, which relates to the program area 17, portion of the medium 20, and the PMA 23, the TOC area is in a recorded state. The PMA 13, the TOC area 15, and the 25, the program area 27, and the area 29 are disposed one by lead-out area are referred to as a file information area. The one in an outward direction. program area 17 and the user area are referred to as a data The TOC area 25, the area 29, and the PMA 23 are in aca. 55 unrecorded State and in a recordable State. Prescribed user Control data and user information can be recorded in the information or requested user information is already PMA 13 and the program area, respectively, using a CD recorded in the program area 27. In addition, a password Writing drive, Such as, for example, a commercially avail may be recorded in a predetermined portion of the optical able CD-R or CD-RW drive. Alternatively, the medium 10 recording medium 20. The predetermined portion may be in may be a hybrid-type medium that includes a record-able 60 the information area or a portion inside the information area area and a ROM (read only memory) area in which pits Such as, for example, a portion outside the lead-out area, the corresponding to user information are previously formed innermost portion of the TOC area, or the innermost portion using a Stamper. In addition, the medium 10 may further of the PCA, etc. include an additional area Such as a PCA (power calibration Specifically, the optical recording medium 20 shown in area). 65 FIG. 2 includes the PMA 23, the TOC area 25, the program Even in the undesirable case in which an unauthorized area 27 that is in a recorded state, and the area 29 having the user intends to read user information Stored in the program user area and the lead-out area, wherein the PMA 23, the US 6,469,963 B1 S 6 TOC area 25, and the area 29 are in an unrecorded state and control data Stored in the filing information area. In the in a record-able State. The password may be recorded in a recording Step, another drive records the control data in specific portion of the medium 20. another medium. Alternatively, a drive equipped with a Before the medium 20 is distributed to members of the memory, for example a DRAM, may record the control data group consisting of limited members mentioned above, the in another medium after reading the control data of the information provider notifies each member of a password optical recording medium 30. In the erasing Step, the drive that is the same for all the members, and by which the erases the filing information area that Stores the control data. information stored in the medium 20 can be read. The Even if the control data of the. CD-RW medium 30 is provider also notifies the member of PMA (control) data accidentally erased by this erase method, the information corresponding to the user information recorded in the pro Stored in the program area 43 can be read by re-recording the gram area 27. control data which is recorded in another medium in the The group member sets the distributed medium 20 in a filing information area of the CD-RW medium. CD writing drive and inputs the notified password. The CD In another embodiment of the present invention, a higher Writing drive compares the inputted password with the level of secrecy is possible if the control data of a CD-RW password stored in the specific portion of the medium 20. 15 medium in which the control data has been erased by the When the inputted password is verified, the drive becomes above-described method is stored in another medium which able to write to medium 20. is kept physically separate from the CD-RW medium. Next, the member records the correct PMA data in the FIG. 6 is a block diagram showing one embodiment of the PMA 23 using the CD writing drive. The member finalizes information recording/reading System constructed according the medium 20 by recording TOC data in the TOC area 25 to the present invention. An input device 65 Such as a corresponding to the recorded PMA data. Alternatively, the keyboard or a mouse is disposed So that an operator can member may finalize the medium using a computer installed control read, record, and initialization functions to a CD-RW with Software for directly recording the TOC data in the medium. In addition, information needed for the controlling TOC area. In this case, the member inputs the notified PMA system is transferred to the system by the input device 65. data to the computer. By this procedure, the finalized optical 25 A CD-R/RW unit 62 includes a CD-R/RW drive and an recording medium 20 becomes readable or playable by CD optical recording medium Selected from the group consisting drives. of CD-R medium and CD-RW medium. An external data In addition, when the information provider distributes Storage unit 67 includes another drive capable of read and Specific information to a specific group member, other than write operations and another medium that Stores control data common user information available for every member, for access to the user information Stored in a program area another optical recording medium 30 of the present inven of the optical recording medium. tion as shown in FIG. 3 may be used. An area 29A of the A system comprising a CPU (Central Processing Unit) 60 optical recording medium 30 is a portion in the program area controls the input device 65 through a bus 66, a display in which specified information is additionally recorded by control device 64, a RAM (random access memory) device the provider using a CD Writing drive. PMA data regarding 35 61, and the CD-R/RW unit 62. A command to begin a the additionally recorded portion of the program area is prescribed operation is inputted by the input device 65 to the distributed to the specified member. The member then inputs system. The system then transfers a program to the RAM 61 the password and the specific PMA data to finalize the from the external data Storage unit 67. Programs for oper medium 30. Thus the medium 30 becomes readable or ating the erase method of the present invention, or other playable by CD drives. 40 programs for recording and reading information are housed Even if the medium 30 is handed to an unauthorized user, in the external data storage unit 67. The RAM 61 tempo the unauthorized user cannot read the user information, rarily Stores Such programs or various kinds of information, because the outsider is not notified of the password nor the which are required for recording and reading information of PMA data regarding the additionally recorded portion. the CD-RW medium, when the system operates. Therefore, the secrecy of the information contained within 45 The display control device 64 controls a display 63 such medium 30 is maintained at a high level. as a CRT (cathode-ray tube) display or LCD (liquid crystal In addition, when a specific password is provided for a display) such that the program stored in the RAM 61 and Specified member other than the common members, the window images and icons related to various functions of the Specific password may be used to cover a variety of acceSS 50 program are displayed on the display 63. The external data ranks among the members. In this case, information relating Storage unit 67 also stores data for recording or data required to the additionally recorded portion of PMA can be read for operations of the System, in addition to the program for using the Specific password. Accordingly, the Specific infor operating the erase method of the present invention and the mation is not disclosed to members having a lower acceSS program for recording and reading information to and from rank, thus increasing the level of Secrecy by limiting infor 55 the optical recording medium. mation access within the group itself. The CD-R/RW unit 62 includes another CPU and another FIGS. 4A and 4B are schematic diagrams respectively RAM to record, read and erase information in the CD-RW showing structures of a CD-RW medium before and after medium in accordance with a command from the CPU 60. information is erased by a quick-erase method of the present FIG. 7 is a flowchart illustrating one embodiment of the invention. With reference to FIGS. 4A and 4B, one embodi 60 erase method according to the present invention. The erase ment of the erase method according to the present invention method is further explained hereafter with reference to FIG. is described hereinafter. 7. In FIG. 4A, reference numerals 41, 42, 43, and 44 When a CD-RW medium is set on the CD-R/RW drive in designate a PMA area, a TOC area, a program area (data the CD-R/RW unit 62, as shown in FIG. 6, the CD-R/RW area), and a lead-out area, respectively. 65 drive reads control data stored in a filing information area (a The erase method includes a reading Step, a recording PMA and a TOC area) of the medium, and records the Step, and an erasing Step. In the reading Step, a drive reads control data in another medium in the external data Storage US 6,469,963 B1 7 8 unit 67. Subsequently, the control data stored in the PMA lead-out area of the CD-RW medium So that CD drives can and the TOC area of the CD-RW medium is erased and the read the information stored in the CD-RW medium. If access lead-out area of the CD-RW medium is erased. Using this is allowed only when the additionally recorded system procedure, the control data in the filing information area of information is verified of the current system information of the CD-RW medium is erased, resulting in completion of the the System being used, the Secrecy of the information Stored CSUC. in the CD-RW is improved. The CD-RW medium, which has been erased, is identified Further, when an application program and an installation as an unrecorded medium by an information recording/ program are recorded in the program area 43, the Secrecy reading System. Therefore, new data can be recorded on the can be improved using a method in which the application medium. program can be installed only when additionally recorded Alternatively, the information Stored in the data area can System information is verified to be the same as the System be readby re-recording the control data Stored in the external information of the System being currently used. data Storage unit 67 to the filing information area of the AS described above in detail, the present invention pro CD-RW medium. This operation can be performed only by vides a novel optical recording medium, erase method, and a person who can access the control data. 15 information recording/reading System. The program area may be recorded using a writing drive The optical recording medium of the present invention that is capable of recording on an optical recording medium. has a high level of Secrecy for user information Stored Alternatively, the medium may be a hybrid-type medium therein. that includes a recordable area and a ROM (read only What is claimed is: memory) area in which pits are previously formed using a 1. A method for erasing information contained with a Stamper. CD-RW medium, said method comprising the steps of: In addition, when the control data is required to be re-recorded to the PMA area of the erased CD-RW medium reading control data Stored in a filing information area of a CD-RW medium; the following method can also be used. As shown in FIG. 5, 25 System information that is peculiar to the System is recorded recording the control data in another medium; and in the data area (program area). Then the control data need erasing only the control data in Said filing information to access the System information and the user information area of said CD-RW medium. stored in the program area is recorded to the PMA 41. Control data is then recorded in the TOC area and the